


On Water's Edge

by DisgruntledMinion



Category: Kuroshitsuji | Black Butler
Genre: Alternate Universe, Blood and Gore, Dubious Consent, Dubious Ethics, M/M, Magic, Minor Character Death, POV Alternating, Past Tense, Present Tense, Violence, merman
Language: English
Status: Completed
Published: 2017-05-13
Updated: 2017-05-27
Packaged: 2018-10-31 10:19:42
Rating: Explicit
Warnings: Graphic Depictions Of Violence
Chapters: 3
Words: 20,274
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10897308
Author URL: https://archiveofourown.org/users/DisgruntledMinion/pseuds/DisgruntledMinion
Summary: Ciel meets Sebastian when he's barely a year old. Meets being a relative term, as he can’t remember the initial encounter, but everyone around him tells him the story as he ages so that it’s stuck in his mind. Burned there. Like the familiar mark burned on the back of Sebastian's hand.





	1. Chapter 1

**Author's Note:**

> **Spoilers at the bottom in regards to the dubious consent tag that will occur in chapter 2. It's non-sexual in nature, but if you're worried this might affect you, please read the notes at the bottom for clarification.**
> 
> AN: I was sorely craving merman Sebastian and couldn't find any quick enough to sate my craving, so I wrote one instead, lol. It was supposed to be a simple, funny story in a new, experimental style and in typical fashion, it ballooned to 20K worth XD Please note that the sections alternate between present and past tense, and different POV's as well. 
> 
> Final notes: Unbeated, so please ignore any mistakes :)

**.:|On Water's Edge|:.**

Ciel meets Sebastian when he's barely a year old. Meets being a relative term, as he can’t remember the initial encounter, but everyone around him tells him the story as he ages so that it’s stuck in his mind. Burned there. His mother tells the story factually and without garnish, while his father tells the story with flare, but remains mum on additional stories that occur during Ciel’s infancy. Sebastian though, takes great pleasure in relishing stories to Ciel. Sebastian’s stories however, always include something his parents never offer. A different perspective. His eyes dance with laughter and his hands swim about the air as he talks, gestures for everything and strange words littering his speech. 

It’s enough that some of Ciel’s earliest memories involve Sebastian, even if he can’t remember that actual first meeting. He finds himself content with that knowledge though; comfortable in knowing that Sebastian can fill in the blanks when he asks and isn’t afraid to tell the tale. 

_「It starts like this.」_

Years before Ciel’s birth, his parents purchase land alongside a sprawling lake, located deep within the country. His father, a successful CEO for a toy company and mother, a part time fashion designer, part time entrepreneur and full time happily married wife. 

They purchase the land to escape the crowded city life and hope to find inspiration to further their careers. And at the price they pay for the property, they couldn’t be happier. They ignore the rumors and whispers that linger over the property like a haze. Crazy words that spoke of people and animals vanishing without warning and of creatures that lurked in the depths of the supposedly picturesque lake. 

Dogs slipping into the lake and drowning, Vincent claims and they think nothing more of it. Accidents happened and tongues wagged more than necessary when people lived in a small town with nothing but gossip to fuel the entertainment. So they brush off the words and focus on their companies, watching with pride as they flourish underhand.

And so does their family. So that three years after moving into their new lake retreat, the cries and laughter of a child fill the air in the crisp winter months, when the lake seemed dead and devoid of life. With only the occasional ripple of water on the surface to break the reflective stillness. 

Baby Ciel grows fast –the apple of his parent’s eye and their delight in the world – despite ails of small bouts of asthma that flare up on occasion. And so the winter months roll into spring, flowers sprouting from the hardened earth to grace the skies with their colorful blooms until the final frost thaws away, leaving the cold behind and welcoming summer. 

Summer hits with warm temperatures, driving the family to the water’s edge to enjoy the sparkling lake views that surround them. Fish dart about just below the surface of the water, enticing Ciel to laugh with delight as their scales glitter off the sun’s rays as he watches them from the dock.

His parents watch him carefully and with love as he babbles at the fish in adorable baby talk. Cooing and smacking soft hands against the worn wood on the dock. They smile at each other, excited and charmed in ways that only new parents can, until the heart stopping sound of a splash tears the happiness from them in the span of a heartbeat.

Later, they’ll refer to it as The Incident (capitalized even in speech, because it’s a resounding event that will forever change their lives). 

They rush to the edge of the dock, Vincent already yanking his shirt over his head and ready to dive in after Ciel, only to find the child _floating_ on the water’s surface. He’s soaked through, but looks no worse for the wear and laughs hysterically, completely unaware of the years he just shaved off his parents life. 

And then a head pops up out the water. Vincent screams and Rachel stares. Ciel laughs all the more, as he reaches chubby hands towards the head. No, person. It’s attached to a body after all – and years later, Vincent will adamantly protest that he knew that and that ‘no, I didn’t scream Rachel, thank you very much.’

The person holding Ciel drifts closer, but not before running long fingers over Ciel’s face. As though in fascination. It’s enough to give Ciel’s parents pause and Rachel wastes no time snatching her baby from the strangers arms. Perhaps, had she taken the time, she would’ve noticed the glittering scales splattered across pale forearms and the long fin that stretches along the underside of the man’s arms.

“Thank you,” she says as she checks over Ciel. Her baby boy babbles happily at her in her arms, content and safe despite his earlier tumble.

The man stares at them, makes a noise not unlike that of a dolphin, and arches back into the water. It’s a long, drawn out motion that exposes the man’s stomach – Rachel doesn’t stare, don’t say such things Vincent – and a stretch of pale skin all the way to sharp hipbones. Until that gives way to discolored skin and scales, before it settles in their mind that what they’re looking at aren’t legs but instead a tail. A long, dark red tail that fans out to a wide, flowing dorsal fin before it vanishes back under water.

Turns out those glittering fish that originally caught Ciel’s attention weren’t fish after all.

**.:|On Water’s Edge|:.**

“I still do not understand the appeal of it,” Sebastian admitted, cocking his head at the device in question. “If you prepare the meat properly the night before, you should not need a…a…this thing, to speed up the process.”

“It’s a flame thrower, Sebastian,” Bard said, grin stretching wide across his lips. “Didn’t you ever want one as child?”

“No,” came the deadpanned answer. “I can honestly say it never crossed my mind.”

From across the yard, someone snorted. “Are you telling me that you wanted one as a child, Bard?” Ciel questioned. He tossed the rag in a nearby bucket after giving the clean car an appreciative glance. “That I’ve gone and hired a pyromaniac?”

Bard shuffled under the intense stare. “Well, no. Not really. I mean, I wanted one yeah, but I’m not a pyromaniac.” A pause. “Okay. Maybe a bit. But fire is cool! You can do so much with it.”

Blue eyes flickered over to Sebastian. “Same with water,” he said.

Bard flapped a hand at them. “Not as much as fire,” he exclaimed. “Water is boring.”

Sebastian’s face hardened. “Just for that, I am definitely banning that contraption from my kitchen. The kitchen.”

“Might as well be your kitchen, seeing as no one else here knows how to cook properly,” Ciel muttered.

“I resent that!” Bard shouted and turned back to coo over the machine. “Fine. If I can’t keep it inside, then how about outside? For the grill?”

Sebastian pinched the bridge of his nose. “Fine. I can live with that. Just store it somewhere safe and out of my way.”

Bard punched the air in excitement and wheeled the device away, cackling the whole way. Ciel watched him go and then turned to Sebastian once he rounded the corner of the house. “Why did you just agree to keep that monstrosity? You know he’ll burn down the place and my mom’s gardens.”

Crimson eyes regarded Ciel. “Protection,” he answered after several minutes. “Barriers only work so well and I feel better if we have another layer of protection. It is almost the new moon.”

Ciel nodded in understanding. The night grew the darkest during the times that the moon vanished from the sky, enticing beings from the shadows to slink out from hiding to wreak havoc on the lands. Threatening to devour anything in sight. Be they human or otherwise.

Regardless of what they were, danger always lurked in the world.

He sighed. “Thankfully the company picnic isn’t for a few more weeks.” Ciel looked up towards the sky and heaved another sigh. “I need to go into town today to check on the status of a couple items. If I leave now, I might not hit traffic going into the city.”

“Or you could stay,” Sebastian suggested. “You just came back from a work trip a few days ago.”

His hand made an aborted move, almost as if Sebastian wanted to reach out and grab him but quelled the urge at the last minute. The action made Ciel smile and he reached for the other man instead. “I won’t be long this time. I should be back before it gets dark tonight. It’d be easier if we lived closer to town, but it is what it is.”

A soft noise left Sebastian’s throat. “You could move out there if it is easier for you. Be closer to your company. It will make things better.”

Ciel’s face fell. “Oh, oh no, Sebastian I didn’t mean it like that,” he exclaimed. “I wouldn’t move back to the city for anything. My place is here. With you. No. I can’t stand the thought of moving out there and giving up everything I have here just for an easier commute. It’s not ideal at times, but it’s worth it.”

Sebastian hummed, in what Ciel hoped was understanding. He found it almost amusing how uncertain Sebastian could turn at times despite his strength and possessiveness when it came to him. Ciel chalked it up to the other man’s upbringing and found it one of Sebastian’s more endearing traits.

"Who all will be here for the picnic?” Sebastian asked as they started to make their way around the back part of the house and towards the boat shed. 

Ciel shrugged. “The Board will be here in the morning, and then the rest of the staff will come later in the day. We’ll have at least a hundred people here at one point in the day.”

Sebastian’s nose crinkled. “That is a lot of people in one location. I could not imagine that many people or creatures in another place.”

A hum. “It’s not usually like this,” Ciel said and then paused. “No. That’s a lie. It’s actually normal to surround yourself by a large number of people each day. When you’re younger, you go to school and once you graduate school, then you go to work. Schools have hundreds of people in them and some office buildings have just as many.”

“I would not like that,” Sebastian answered. “It is too…crowded.”

Ciel squeezed his hand. “It’s only like that outside of the home. Once you return home, the number drops significantly. Bar neighbors of course, but you don’t have to interact with them.”

“Still,” Sebastian mused. He looked at Ciel, red eyes almost glowing under the sunlight. “I like this better.”

“The two of us?” A hand swept out over the lake and the surrounding area. “Or this?”

Sebastian grinned, a hint of teeth digging into soft flesh. “Both.”

Ciel chuckled lightly at the answer. “Of course you would,” he said. He dug into the folds of his shirt, pulling out a chain that hung around his neck. At the bottom, an old bronze key looped through the polished silver and seemed to pulse with energy. Ciel fingered the key before palming it as they approached the boatshed. “Then again, I like it too. But I’m biased.”

A low hum vibrated out of Sebastian’s throat as Ciel jammed the key into the door to the boatshed. “Will your guests have access to this area?”

“No,” Ciel said quickly and gave a negative shake of his head at the same time. “I already sent out a message noting which locations the guests cannot access.”

“Thank you,” Sebastian answered. He stepped inside the boathouse behind Ciel and shut the door with a resounding sound. The lock clicked under his hand and he released a deep sigh, body shivering as the silence of the room surrounded them.

Ciel watched greedily as Sebastian tugged at the collar of his shirt, exposing pale skin and the long stretch of his neck. If he looked just so, he could see the skin turning red as it traveled down the length of his neck before vanishing underneath the shirt Sebastian wore.

He leaned back, hoping for more of a show and frowned when Sebastian didn’t appear in a hurry to take off the rest of his clothing. “Well,” he prompted after several long moments. Crimson eyes blinked at him and Ciel made a gesture with his hand. “As you were.”

A flush worked its way up Ciel’s cheeks at the amused smirk Sebastian tossed his way. “I thought maybe we could savor this moment,” Sebastian said. “We will not get much time together once your party…thing starts.”

Ciel pouted at the words. “Maybe it’s because of that that I don’t want to savor the moment,” he pointed out. “Please, Sebastian? I just want to see you. It’s been too long.”

Sebastian heaved a long-suffering sigh, but Ciel could see the amusement glittering in crimson eyes. And he knew - even without Sebastian having to say so – that Sebastian preferred as little clothing on his body as possible. A kickback to his culture and heritage, more so than his upbringing. And try as he might, Ciel couldn’t bring himself to force Sebastian to accept the change. After everything that happened to Sebastian in their years growing up, it didn’t sit right with Ciel, and he felt it only right to give him the choice as often as he could. Additionally, the mere concept of clothing baffled the other man, as Sebastian once confided to him in their younger years, which lead to the building of the boathouse not long after.

Anything to help keep Sebastian comfortable when he stood next to Ciel.

“If you insist,” Sebastian said finally.

“I do,” Ciel answered with a grin. One that Sebastian mirrored, sharp and dangerous.

**.:|On Water’s Edge|:.**

_「It continues like this.」_

Rachel and Vincent avoid the water’s edge for the rest of the summer. From their windows, they can see the sun glistening on the surface and Ciel wails to go outside, but fear keeps them locked in the house. Throughout the year, they keep a wary eye on the lake, just minutes from their house. They search the water for any motion on its surface, but no red tail or pale body breach the area again. 

The cooler temperatures of autumn and then winter quell Ciel’s fussing to go out near the lake, much to his parents relief. They celebrate his first birthday with much joy and energy filling the air. Troubles momentarily forgotten. Yet as winter creeps away and spring blossoms along the earth again, their eyes turn towards the lake. 

No one reports any missing people throughout the year since The Incident, and suddenly, everyone’s warnings about the property come crashing back to them. They debate for months if they should move back to the city, but the city offers its own challenges and threats. In the end, they remain at the lake and simply keep a cautious eye on the water.

Ciel though, seems unaware of the dangers in the water and loudly demands to go outside near it again. They spend several weeks trying to reason with the toddler, but Ciel refuses to listen. Finally, they compromise. Vincent purchases a pistol and carries it with him as they set out a blanket near the banks. Close enough for Ciel to see the water, but not near enough that their baby boy can fall in again. 

Several days of this pass in succession and through it all, the water’s surface remains calm. 

It's enough to make them relax a bit and part of them wonders if the…creature left the area. Vincent wagers that it sought new territory after realizing someone else lived there now. Rachel nods in her agreement, but silently believes the man still lurks in the depths. It didn’t show fear to them last year and though he gave Ciel back to them, nothing in its actions spoke of it leaving. For all they know, the creature lived there long before them. A fact Rachel leans heavily on.

Another thought lies on her mind as well. She easily recalls the day the man…creature – they both have a hard time calling the thing a mermaid; merman? – saved Ciel. Because that’s what he did. He saved Ciel from drowning and only showed curiosity towards her child. It makes her wonder, in the far depths of her mind, if the – heaven help her – merman isn’t threatening to her family.

It takes another two weeks for Rachel to work up the courage to step foot on the dock again. Ciel remains safely locked up in the house with a babysitter, who has strict instructions to call Vincent and the police if she doesn’t come back to the house in fifteen minutes. The water remains calm but she clears her throat and calls out a tentative ‘hello’. The word echoes off the water but nothing happens.

It’s anticlimactic and makes Rachel wonder if the merman only appears for her child. The thought makes her falter, protectiveness flaring up brightly within her. She wouldn’t risk Ciel’s life to slack her curiosity. 

Then, the water ripples to her right and something launches itself out of the lake towards her. A scream builds up in her throat, but terror keeps it from escaping. As quick as the attack starts, another thing smashes into the first creature. They crash down onto the deck, just steps away from her feet and in the sunlight, dark red scales glitter against pale purple ones.

The two creatures wrestle on the wooden deck, snarling deep within their chest as blood splatters across the planks. Rachel takes two steps away from them, putting space between the wriggling mass of flailing limbs and tails. The merman with red scales bares his teeth against the purple one, and Rachel shudders at the pointed teeth. 

Red Scales shifts his body, swinging it in an arch towards her and Rachel grabs the pistol tucked in the small of her back before she realizes that the merman isn’t trying to harm her. Instead, he’s putting himself between her and the other merman. Her head swims at the knowledge and even though every nerve in her body screams at her to leave, she cannot bring herself to move. 

Because she wants to know how this fight will end. Wants to know if Red Scales will prove an asset to her family. 

The mermen snarl at each other – and looking far more like beached seals than mythical creatures of the water, and the thought nearly makes her laugh, because apparently, this is now her life – both heaving for breath before Red Scales stops abruptly. Long finned ears twitch back, practically quivering. He then pushes his torso up and off the deck without warning, and lunges to the side. He goes into the water with a neat splash, leaving Rachel alone to defend herself from the other merman. 

Coward, she thinks, as she levels the weapon at the other creature as it starts towards her. 

Before she can shoot though, pale arms break the surface of the water at the end of the dock and pull the other merman back into the lake. Liquid splashes over the edge of the dock, and the water below her churns violently as they fight unseen. She can see the ripples making their way out to the center of the lake and with cautious steps; she creeps closer to the edge of the dock.

“Rachel!” a voice calls from behind her. Followed closely by: “Mama!”

The words make her pause, and she thinks back to the way Red Scales paused in his fighting, ears twitching and alert. Realization dawns over her in a start. He diverted the fight underwater where it was not only safest for him, but also for her family. In a way, Red Scales wanted to protect her child from seeing a bloody fight at such a young age. 

She doesn’t look over her shoulder as her husband approaches. The noise underneath the dock tappers to an end and Rachel holds out a hand to stop Vincent from advancing. Her other hand remains steady on the pistol, ready to defend herself if necessary as the water splashes again.

From the edge of the dock, a head pops into view and Rachel startles at the blood that coats Red Scales face. Crimson eyes hold her gaze and, swallowing back any sense of rational, she stalks towards the merman. She needs to know – a need so deep she can feel it in her bones – that the other merman is dead. Needs to know what level of violence this merman went to in order to protect her.

She stops just in front of him and ignores Vincent’s panicked pleas to come back from the water’s edge as she squats down in front of the merman. Deep wounds litter the merman’s chest, oozing blood that turns the water a pink color as it dilutes near his waist. Just at his hips, Rachel can see the other merman bobbing just below the water’s surface. If she looks hard enough – past the blood staining the surface of the lake – she man make out the missing chunk of flesh on the other merman’s neck. She thinks she sees a glimmer of white bone but looks away before she can throw up.

Through it all, Red Scales hasn’t moved and his eyes flicker between her face and Vincent behind her. His eyes seem to linger longer on Vincent, and this time, Rachel does glance over her shoulder. In Vincent’s arms, Ciel squirms and wiggles to get down, and understanding dawns in her mind.

She stands up and goes over to Vincent, plucking Ciel out of his arms without much warning. Vincent sputters and rightfully so, starts to panic. But she has a good feeling about this and Ciel is waving his arms around, exclaiming ‘fish, fish, fish’ as they get closer.

Red Scales vanishes from view briefly before reappearing again with a clean face – and Rachel can only hope she hid the body at the same time. He grips the edge of the dock as Rachel lowers Ciel down so they can meet each other.

“This is Ciel,” she says. Red Scales makes a clicking noise, almost as though he’s trying to say Ciel’s name. He looks intrigued but careful as he reaches out to run a webbed finger over Ciel’s foot. The merman marvels over the soft, chubby flesh and in return, Ciel giggles loudly. 

Rachel holds her breath, terrified out of her mind that Red Scales will snatch Ciel from her grasp. However, the merman remains careful and tender with his exploration. He even tolerates Ciel examining his face and only winces when small hands grab at his ears. 

“Easy,” Rachel murmurs to Ciel, guiding his fingers in a gentler motion so that they can both touch the webbed material that frames the merman’s ear. It’s scaly, like that of a fish, and it moves underneath her hand as though the soft touches tickle.

Yet through it all, the merman never lashes out or attempts anything violent. She’s not sure if it’s because Vincent hovers nearby or that she has a weapon within reach. Rachel’s seen the strength in his coiled muscles and knows what he can do. A gunshot might hurt, but if it’s not in the right spot, she doubts the pain will slow him down much.

Ciel babbles nonsense to the merman, who answers in turn with chirps, whistles, and clicks. Neither can understand each other, but Ciel still seems to enjoy the undivided attention. Rachel lets them talk, cautious but nerves still soothed. For now, it appears that Red Scales won’t bring harm to her family and already, Rachel plans to use that to her advantage.

**.:|On Water’s Edge|:.**

Ciel made himself comfortable on one of the plush cushions that lined the outer wall of the boatshed, tucking his legs up underneath him as Sebastian divested himself of his shirt. The chair creaked as he shifted his weight, drawing Sebastian’s attention, and earning him a wicked grin. Sebastian knew all too well how to play with Ciel, using his weakness – his impatience – to his own advantage. It infuriated Ciel more than he would admit. Although he had a feeling Sebastian knew all too well what it did to him.

He made a needy noise when Sebastian took the time to fold the earlier discarded shirt, taking the effort to smooth out the wrinkles and ensure that the piece of fabric rested safely in a dry spot. Crimson eyes danced with amusement and from where he sat, Ciel could see the smirk growing across pink lips, and Ciel briefly entertained the idea of simply pushing Sebastian into the water. 

He refrained though, knowing that Sebastian delighted in the knowledge that he drove Ciel to brink. Not just to the brink, but beyond that. So much so that Ciel lost composure of himself at times. If Ciel didn’t know better, he would bet that Sebastian baited him purposely, just to see him lose control.

“Explain to me again how you expect this plan to work,” Sebastian said in the quiet of the room. Water lapped against the sides of the boathouse, almost as though the very lake breathed in time with Sebastian.

Ciel blinked. “What?”

Sebastian smirked at him. “The plan,” he repeated. “I still do not understand how it will work.”

Blue eyes squeezed shut and Ciel pinched the bridge of his nose. “Now, Sebastian? Really?” he asked. Because how could he not? Not when Sebastian stood in front of him shirtless, red scales scattered against the stretch of his neck and down his torso. 

“Yes, now,” Sebastian answered. He sounded serious, but Ciel knew better. Despite the severe façade he wore, Sebastian remained quite the trickster. “I cannot protect you and ensure my own plans if I do not understand how this will work.”

Ciel sighed and waved a hand at Sebastian. “I can explain while you finish,” he tried. “Keep going.”

He received a negative shake of the head for his try and Ciel ground his teeth together. “I want to ensure you have my full attention,” Sebastian said. He sounded so sincere that Ciel almost believed him. Almost. “I do not want to miss a thing.”

“Fine,” Ciel bit out, irritation coating his words. “I’ll have the target in my office, under the guise of a meeting, and then you come in and you do what you do best. End of story.”

Sebastian cocked his head. “But I,”

"Sebastian," Ciel hissed and then squeezed his eyes shut at the near wounded look Sebastian tossed his direction. For a moment, he entertained the idea that the merman truly wanted to review the plan to ensure the best execution of it, but then dismissed the thought. Sebastian knew full well how the plan would run, especially seeing as he helped create certain parts.

His eyes fluttered open, taking in the seemingly innocent figure standing before him. Still standing shirtless, with the morning sun glinting off red colored scales. They shone like stained glass, and Ciel longed to reach out to touch them. He tamped down the temptation with a heavy mental foot. He knew that Sebastian wanted to see him break, wanted to tease him until he frayed apart at the seams. Merman – and more so mermaids – enjoyed their tricks. Seducing and enticing their prey until the end. When jaws and sharp teeth closed around them, believing the fantasy up until the last seconds of life. 

Ciel pulled in a deep breath and ran a hand over the lower part of his jaw. He would need to shave tomorrow morning, but he couldn’t bring himself to worry over it this morning. Lazy Friday mornings with Sebastian were the best. Lounging in bed with legs tangled and enjoying the way the early morning light crept through the curtains to crawl across the room. Lazy Friday mornings meant teasing and exploring fingers, and warm – but rank smelling – kisses and tender touches. 

“Right,” Ciel answered before his imagination could get the better of him again. “The plan.”

Sebastian simply grinned at him, sharp teeth and wicked intent in his eyes, as though he knew exactly what Ciel just thought moments prior. “Yes. The plan.”

Ciel flapped a hand at the merman. “Well if you would hush for a moment, I could explain the plan. Again.” He gave Sebastian a point look but received only a gleeful smile in return. “We know that someone plans to sell some blueprints to one of our competitors. I just, much to my dismay and eternal frustration, haven’t been able to find out which individuals plan to do so.”

“And our informants placed in the rival companies informed you of this,” Sebastian said. A furrow formed between his eyebrows. “We are sure that they have not turned on you and are not feeding you lies instead?”

“I’m sure,” Ciel answered. If only because Sebastian pointed out the very same question when they first learned of the betrayal within the company. Playing the corporate game meant taking chances and hoping those loyal to the company stayed loyal. Ciel picked the best and closest to him to infiltrate those companies that sought to see him empire tumble. He blinked at Sebastian. “You tested them yourself. They’re loyal.”

A low hum sounded throughout the boathouse and Sebastian’s hands fell to his waist. Long fingers fiddled with the belt before pushing the leather through the buckle. “I did. I tested them again after they brought you that information as well.”

Ciel paused, both because of Sebastian’s actions and due to his words. “You did?” he pressed. He found himself oddly touched by the concern that the merman went through to ensure loyalty to Ciel. “I don’t remember seeing you, you know.” He waved a hand, letting the motion convey what he couldn’t say.

“I tested them randomly over the following week,” Sebastian said. The belt _clinked_ as he pulled it out of the belt loops, and then set it to the side. It coiled neatly and rested safely on top of Sebastian’s shirt. “I had to ensure they did not pose a threat or danger.”

The _‘to you’_ remained unsaid but hung heavily in the air. Ciel knew all too well what happened to those individuals that proved dangerous to Ciel or anything related to him. His family, his company, and his friends. A fine shiver worked its way up Ciel’s spine at the thought and he could only hope that Sebastian would’ve informed him of any betrayal before he took adverse action.

“So we know for sure then that someone plans to sell company secrets,” Ciel said instead, pushing aside any unease in favor of watching Sebastian. Black slacks slung low on his hips, hipbones peeking just over the waistband and Ciel forced his eyes back up to Sebastian’s face. Best not to put into practice what he truly wanted to do.

“Yes. Which leads us to your current plan.”

“Correct.” A pause. “We’ve narrowed it down to one person for sure, but I suspect they’re just a minion. I want the ringleader.”

Sebastian made a confused sound and Ciel melted in his chair at the sight of Sebastian’s perplexed expression. It made him want to pull the merman closer and stroke back his hair, soothing away the crease between his eyebrows, while protecting him from the cruelties of the world. Ciel frowned at the thought, shook himself from the stupor, and then glared at the merman.

“Stop that.”

Crimson eyes blinked and Sebastian gave himself a small shake as well. “Apologizes. I did not think.” He trailed off.

“It gets stronger when you’re closer to the water and your shifts,” Ciel said. “What had you confused?”

“What is a ring leader and why would anyone wish to lead a ring? It does not make sense.”

Ciel giggled, unable to help himself. “It’s an expression. Someone who initiates or starts an activity. Usually an illegal one.”

Sebastian frowned, mulling over the words and Ciel watched with joy. Like witnessing a child learn something new. The discovery of learning. The way eyes lit up in understanding, or the puzzlement of trying to decipher the new item in front of them. Most times, Sebastian grasped ideas and concepts without issue. Expressions though remained a bit trickier and already, Ciel could tell that Sebastian wouldn’t solve the new puzzle, but he looked damned cute trying.

“I suppose,” he said finally. “I still do not understand why someone would involve rings though.”

Another giggle and Ciel leaned back in his chair. “Anyway,” he said, forcing the conversation to continue. “I’ll bring in our suspected target and speak with him at some point during the company picnic. It’s imperative that we keep an eye on him without making him feel as though we’re on to him. It could ruin everything.”

Sebastian nodded in understanding. “You speak with him for a while, and then I will come in.” His hands thumbed the button on his pants before popping the little knob. “How will you signal me? Or am I to assume when I should enter the room?”

Ciel threaded his fingers together and set them on his lap to keep from pantsing Sebastian where he stood. “I’ll have to signal you somehow with a specific phrase. If you come in too early when he’s not relaxed enough, then it will make things more difficult to extract the information from the target.” He fiddled his thumbs. “Once he seems calm enough, I’ll bring you in and that’s when you do your thing. I need him to give us answers, Sebastian. We’ve sat still for all this time, bidding our time, and have little to show for it. I don’t want our mole to vanish under our noses.”

He spent too many hours sorting through files and watching employees to let their little hunt drag on for much longer. It remained important that they pinpoint the correct person – or persons – responsible for stealing from him, but not at the cost of negatively impacting the company. And for too long, Ciel felt as though the thief mocked him. Dangling the answers in his face but always out of reach.

“Understood,” Sebastian answered. “I will not let you down.”

Lips quirked up before Ciel could stop himself. “I know you won’t,” he said. “You haven’t yet.”

“I try,” Sebastian said, and Ciel’s eyes narrowed in on the curve of a sharp hipbone, standing out in stark relief to the dark pants Sebastian wore. ”Is that all?”

A hum and Ciel forced his gaze back up to Sebastian’s face. “If you don’t have any other questions, then yes. You were the one who wanted to go over the plan again, even though I swear you knew it.”

Sebastian shook his head. “I do not have any other questions regarding the plan,” he said. 

Fabric hit the wooden boat deck, landing with a muted _thump_ as the pants landed in a pile at Sebastian’s feet. A _splash_ sounded a second later and water crested the edges of the boat dock, wetting the surface just shy of soaking Sebastian’s pants. Ripples continued to develop on the water as they moved out to the edges of their reach while the remaining surface cleared, and Ciel snorted.

“Cheeky bastard,” he said, staring at the water. His eyes drifted back to the puddle of fabric that rested just next to a large puddle, where he could just make out the _Star Wars_ themed boxers nestled within the pants.

Briefly, Ciel wondered if it should concern him at the speed at which Sebastian could divest himself of clothes when prompted, and then shook his head at himself. Sebastian did what he wanted and no one could make him do what he didn’t want. If he didn’t want Ciel to see him nude, he would’ve done so. And Ciel knew for a fact that Sebastian preferred the buff over clothing, another kickback to his heritage - hence boxers over briefs, even though Ciel told Sebastian repeatedly that boxer briefs offered more comfort. 

No, Sebastian planned his little strip tease the moment Ciel set eyes on him when they entered the boatshed. Knowing what Ciel wanted and offering him small tastes, but never allowing him the luxury of a full meal. Yet Ciel didn’t expect anything less from Sebastian. The trickster in him, and the coy but seductive side of him, remained his true personality. An even truer disposition of his kind and one that Ciel could never hope – or want – to curb.

**.:|On Water’s Edge|:.**

_「They grow together like this.」_

Rachel hires two people. A sign language teacher and a specialist. The first one proves easiest to find. The second however, takes the longest to track down. Her theory with the specialist though runs like this. If two merman exist in the lake, then more likely exist. In their lake and in others. Probably the ocean as well. That means that someone out there knows of their existence and has knowledge on them.

Her hunch pays off in the end. Undertaker – and yes, the name did give her pause, but given what all she’s seen, she takes it at face value – arrives at the lake house within two days of receiving her message. She escorts him to the lake where Ciel – now five years old – sits on the dock talking with the merman. 

Sebastian. She corrects herself. Because that was his name.

It took years before both Sebastian and Ciel could speak in sign language, to which, Red Scales finally gave his name. She finds that it’s fitting of the merman and for a moment, she pauses to watch as the two speak through rapid hand gestures. Ciel grasped the idea of signing quickly, finding it similar to a game. And once Ciel started picking it up, so too did Sebastian. 

“Well?” Rachel asks. “Your thoughts?”

Undertaker regards Sebastian carefully, the latter returning the look with a fierce intensity of his own, before he grins. “You have a fine merman here,” he says to her. To Sebastian and Ciel, he asks them if he can examine Sebastian closer.

Ciel looks hesitant, and only grants permission after firing off rapid hand signals to Sebastian. Permission given, Undertaker moves closer to the docks edge and laughs lightly at the merman’s attempts to appear threatening but still compliant.

“He’s very territorial,” Undertaker says to her. “Of his territory, of your son, and you. I’m sure that also extends to your husband as well.”

“I thought it was always just Ciel,” Rachel admits. If anything, she believed the Sebastian tolerated them at best. It’s pleasant news nonetheless. 

Undertaker clicks his tongue. “He sees you as family. A pod, if you will. Ciel is the youngest and most vulnerable, so he strives to protect him as best he can.” He cocks his head and makes several clicking noises that seem to come from deep within his throat. Sebastian perks up and responds back in turn. “Ah, there you go.”

Ciel jumps to his feet. “How’d you do that?” he demands.

A wide grin stretches across Undertaker’s face. “Years and years of practice. He has a beautiful voice. Lovelier singing voice I bet.” He pauses. “Or have you heard that yet?”

Rachel shakes her head. “He’s never spoken. Human, at least. We hoped to fix that?”

Undertaker hums back. “Merfolk don’t have developed vocal cards for talking. At least in the same manner that we do. You can’t talk with a mouth full of water, so they have no need to use their vocal cords for human speech.” He leans back on his heels and chirps out a few sounds. Sebastian responds and Ciel looks utterly enthralled. “That’s not to say, of course, that he can’t learn.”

“And the other thing we discussed on the phone?”

Undertaker regards her carefully as behind them, Ciel tries his best to whistle at Sebastian. Whatever sound he makes results in Sebastian responding in a beautiful but eerie noise that instantly has Rachel’s shoulders relaxing and has her thoughts muddled. She feels at peace and calm with herself despite the strangeness that surrounds her, but she can’t bother to question why she feels the way she does.

A _splash_ pulls her from her stupor and her heart seizes in her chest at the sight of the empty dock. All the calm from before tears from her mind with a violent tug and she’s suddenly reminded that Sebastian has the ability to spirit her child away without warning.

She finds herself at the edge of the dock just as Ciel pulls himself out of the water. Wet, but no worse for the wear. Sebastian pops up a second later, an entertaining mix of amused and frustrated. 

“I fell in,” Ciel chirps. He squeezes the water from his pants and pats Sebastian on the head, earning a disgruntled grunt from the merman. “Sebastian saved me. Again.”

Undertaker chuckles lowly next to her. “He didn’t fall in on accident,” he says. “You have a strong merman there.”

Rachel spins around to eye him. “Did Sebastian pull him in on purpose?”

“No. Completely accidental on his part,” Undertaker says. “Mermaids sing to ensnarl their victims or protect themselves. Mermen have something called a thrall, which enables them to lure others into a sense of calm and peace. In some cases, it lures people closer to them. The noise you heard earlier from him? That was Sebastian’s thrall.”

“Is it dangerous?” Rachel asks.

Undertaker shakes his head, pauses, and then shrugs his shoulders. “To your family, no. To unwelcome people, very much so.” He gestures to Ciel. “Sebastian went into the water right away when Ciel fell and rescued him. Someone else though? If they posed a threat to his territory – or his pod – you wouldn’t find evidence of them come morning.”

Rachel shivers. “I wasn’t aware.”

“Most aren’t,” Undertaker admits. “It’s kept secret for a reason. Knowing that, are you still certain you want to try what we discussed earlier?”

She watches as Ciel spreads his toes out in front of Sebastian, laughing in delight at the merman’s confused expression. Even after five years, he still struggles to understand feet and legs. A trait Rachel finds more humorous than she should. The merman lifts his tail up out of the water, letting the sun hit the scales just right so that the beams bounce off the lakes surface. 

“Yes,” she answers after turning her attention to them. “We have enemies from our line of work. I want to make sure Ciel has someone loyal at his side. Someone who will watch out for him when we can’t.”

“A guard dog.”

“If he must be.”

Undertaker giggles, the noise out of place on such a tall man. “You flirt with danger, Mrs. Phantomhive,” he says. “But yes. It is possible.”

Rachel sucks in a deep breath and exhales slowly. “Do it.”


	2. Chapter 2

**Notes for the Chapter:**

> AN: Second chapter! I increased the chapter count, because this section was long (about 13K worth), and I thought it would flow better if I separated it into an additional chapter :)
> 
> Warnings for violence, gore, and minor character death in this chapter. Additionally, please note that the dubious moral/ethics comes into play during this chapter.

**.:|On Water’s Edge|:.**

A pained hiss left Sebastian’s mouth as he eased his body lower into the water. Faint ripples moved across the water’s surface and away from him, as though the very water itself wanted to escape the pain he felt. Sympathetic in ways that human beings weren’t.

Soft pants filled the room and Ciel watched as Sebastian tossed his head back, exposing the long line of his neck. Tendons stood out against pale skin as he ground his teeth together and squeezed his eyes shut; sweat beading up along his hairline. A faint droplet of liquid gathered at the corner of one eye and Ciel traced its motion as it slid down the curve of Sebastian’s cheek. 

Times like this, he cursed his mother for what she did to Sebastian all those years back. The pain that he endured each time he made the shift from merman to not quite human, and back again never sat well with Ciel. Especially as he grew older and witnessed firsthand the agony that Sebastian suffered with each shift. 

The way Sebastian laid prostate on the floor of the boatshed, his lower half resting in the water – because he swore the water helped ease the pain a fraction – as his body tore itself apart, taking one limb and somehow forming two functioning ones. So that the scales _slithered _back into Sebastian’s skin instead of shedding away and his bones cracked apart, growing and stretching existing bone to force the shape of a new limb. Followed by muscle, ligaments, and skin wrapping about the bones, giving the legs shape and their power. And all the while, Sebastian gasped and panted for breath against the floor, his pain trickling down his cheeks until the process finished. Even then, it would take at least another hour before Sebastian could move again. Leaving the bloody, pink tinted water to stand on unsteady newborn legs; like a foal born into the world.__

__Yet each time, Ciel couldn’t bring himself to stop Sebastian from changing. Because as a human – at least human in shape – Ciel could spend more time with Sebastian. He could take him into the city and show him new sights. They could spend hours playing chess inside the house, or wandering about the farmers market, looking for exotic ingredients for a new dish Sebastian wished to make. Because, if only for a short while, Ciel could pretend that Sebastian was human. That he belonged on the land with him._ _

__Until Sebastian started to grow anxious and fidgety, tossing longing looks towards the water. Until his skin grew so dry and cracked that even soaking in bathtub or standing under the stream of a shower, did nothing for the itchy, flaking skin. So much so that even the simplest of motions sent blood to the thin surface and trickling down damaged flesh._ _

__The only cure was for Sebastian to return to the water from where he came, and Ciel had to watch the process start anew. The quiet, almost muffled screams that slipped past Sebastian’s clenched jaw as two human legs melded into a single limb covered in scales. The human skin searing away as bones cracked and fused to form a new shape, while new scales shredded tender flesh as they grew back into place. It left for a bloody mess once done._ _

__His mother paid the price with hers and Sebastian’s blood, and now each shift demanded a blood payment. Morbid, cruel, and selfish._ _

__So long as the pentagram remained burned into Sebastian’s flesh, he would pay a blood price to shift. So long as Sebastian wished to walk alongside Ciel, he suffered in silence. A price that the merman seemed willing to pay, Ciel reminded himself each shift. If only to help ease the looming guilt that hung overhead and gnawed at his stomach when Sebastian bit back pain filled screams to keep from drawing attention._ _

__Because, in the end, Ciel was just as cruel as his mother was. He didn’t force the changes or for Sebastian to join him on land, but he didn’t discourage them either. He let Sebastian suffer for his own greed and selfishness, unable to imagine a world without the merman at his side. If he truly loved Sebastian, Ciel needed to let him go. Break the bond, as it were._ _

__Instead, Ciel clung to the knowledge with greedy hands. Fingers tightening like a snarl around Sebastian, ensuring that he couldn’t escape._ _

__A low whimper sounded from Sebastian’s throat and his body sagged, as though someone cut the very strings holding him upright. From where Ciel sat, he could make out the thick, dark red tail flicking about in the water. It vanished the next moment as Sebastian sunk under the water without a sound or trace that he was there previously. The water stilled, calm and reflective like a mirror, but still dark and inky in the shadows of the boathouse._ _

__Minutes ticked by and despite himself, a trickle of worry wormed its way through Ciel’s body. He knew Sebastian could breathe underwater. He was a merman after all. It didn’t stop the fear though that one day, the shift wouldn’t work properly and Sebastian’s gills or lungs wouldn’t form correctly. An unfounded fear, according to Undertaker when Ciel once confessed his concern, as the magic surrounding Sebastian remained steady._ _

__Still, the first few minutes after a shift always left Ciel anxious and edgy. Especially when the merman vanished beneath the surface. On land, Ciel could handle anything. Water though; that remained Sebastian’s domain and Ciel didn’t refute it. Sebastian knew things about the depths that Ciel could never hope to understand. Creatures and patterns, ways of life. Mysteries to Ciel in the way that human life on land remained a puzzle for Sebastian._ _

__He breathed a sigh of relief when Sebastian's head broke the surface with barely a sound. The water still one moment and the next, a head visible when it wasn’t there before. “That’s terrifying, you know,” Ciel said and unfolded himself from the chair to walk closer to the edge of the water. “Like a horror movie or something.”_ _

__“It is how we hunt,” Sebastian answered. “To make noise means to go hungry.”_ _

__Ciel hummed. “Everything feel okay? Gills working fine?”_ _

__Sebastian nodded. “Yes,” he answered and hefted himself up onto the boat deck, teasing Ciel with wet skin and coiled muscles. “Will you stay here tonight after you return from your trip?”_ _

__“If it’s okay with you,” Ciel said, returning the question back to Sebastian. The boathouse belonged to Sebastian, and it felt like intruding to stay on the premises without asking the merman first. Even if the upper part of the house remained specifically for Ciel. A joint living house in many ways._ _

__A smile split across Sebastian’s lips, warm and inviting. “It is fine. I enjoy having you in my cove.”_ _

__Ciel laughed lightly despite himself. He reached for Sebastian, delighting in the glittering scales that stretched up along the merman’s forearm and bled into a small fin. Like a flipper, Ciel once joked to Sebastian, who was less than pleased with the comparison. His fingers traced along the scales and down to the side fin, feeling heat pulse just below the tips of his fingers._ _

__“Beautiful,” he murmured. Sebastian’s ears twitched, preening at the words and Ciel rolled his eyes. “Yes, yes, I know I say it all the time, but I can’t help what’s true.”_ _

__“And humans say that we are sirens,” Sebastian mused. He tilted his head to the side so Ciel could trace along the fine bones that made up his ears. They quivered briefly and Ciel skimmed down to outline the smattering of scales that peeked over Sebastian’s shoulders. “Yet here you stand, speaking the words you do.”_ _

__Ciel didn’t answer; unable to find the words to contradict Sebastian. Such sweet words humans spoke, laced with honey, in order to get the things they wanted. Promises passed off as lies, and malice lingering just under their intent. Funny how so many people called Sebastian and his kind monsters, when more often than not, humans remained more monstrous than they did._ _

__He let his hand fall back to his side with a sigh. “Don’t act as though you don’t enjoy it,” he said eventually._ _

__“Never said I did not,” Sebastian chirped. He reached for Ciel’s hand and nuzzled into the palm, overly affectionate like the cats he enjoyed so much – although one black cat named Soot in particular remained his favorite and lived in the boathouse with him. The very same ones that he secretly fed every day, while Ciel pretended he didn’t know why they had so many damn cats on the property. “I think you are beautiful too,” he finished with a whistle that dropped in pitch near the end; Ciel’s name in Sebastian’s language. It never failed to send chills down his spine when he heard it._ _

__"You must want something," Ciel teased but flushed under the words._ _

__“Nothing,” Sebastian answered and dropped his hand. Under the natural sunlight that streamed in through the windows, the burned pentagram looked almost purple before Sebastian vanished below the water. He appeared again a second later. “Go. You said you needed to go into town. This is not town.”_ _

__Ciel huffed and ran a hand through his hair. “But you,” he started._ _

__Sebastian waved him away. “I will be here still when you return.” He paused and then leered at him. “And I know very well what you wanted if I let you stay.”_ _

__The tips of Ciel’s ears burned but he refused to look embarrassed. “I’m going. But don’t think this conversation is over. I intend to continue it when I come back home.”_ _

__And wasn’t that a funny thought, thinking of the boatshed as home. Although, if Ciel stayed honest with himself, home was with Sebastian. Whether in the boathouse, or in Ciel’s house._ _

__He leaned forward over the water’s edge and pressed his hand to Sebastian’s cheek, reveling in the simple touch. He brushed his thumb underneath a crimson eye, feeling the way Sebastian’s ears trembled against the side of his hand._ _

__The merman surged upwards, catching Ciel’s face between his hands – and leaving Ciel silently marveling at the strength Sebastian had in his tail alone to keep him upright in the water. A soft kiss pressed against his lips, wet and warm, before Sebastian pulled back._ _

__“I will be waiting,” Sebastian murmured. He let go and slid back into the water before Ciel had a chance to say or do anything, leaving only a ripple of water and bubbles in his wake._ _

__“Cheeky bastard,” Ciel muttered but left the boathouse with a grin and a spring to his step._ _

__

____

**.:|On Water’s Edge|:.**

「Rachel’s plan goes like this:」

It takes several months, so much so that it starts to border into a year, before Undertaker finds a person willing to agree to Rachel’s plan. Not to say that the witches themselves didn’t exist, but that the thought of binding a merman to a human and forcing a change upon them provoked more unease that Undertaker original assumed. Finally, though, he locates a witch who straddles the line just this side of dangerous that takes the job with no questions asked. 

She’s attractive, Rachel admits, in a way that most creatures are. Short gray hair that ruffles in the wind as she introduces herself and light purple eyes. They remind her constantly of the pale purple-scaled merman that Sebastian killed all those years back, and Rachel diverts her eyes when she can. The reminder of that day still gives her nightmares at times.

She introduces herself as Angela, and informs Rachel that while she has the supplies needed to complete their transaction, she needs a day to prepare the site. It’s an easy demand to fulfill, and Rachel finds Angela a clear spot near the lake. She watches the witch from afar, deep within the safety of the house where the glass windows offer a semblance of protection – even though Rachel knows well that a house will do little to stop someone from getting something they want.

Angela tramples down the grass, razing it carefully with controlled fire that scorches the earth until nothing remains but a square patch of dirt. Vincent grumbles over Rachel’s shoulder as they continue their vigil, complaining that they’ll have to place more grass seed there once she leaves because it looks as though they just waxed the yard. Rachel rolls her eyes at him in fond exasperation. 

The chalk lines come next, laid down in intricate patterns. The white color stands out in sharp contrast to the newly burnt earth, and even from the distance, Rachel can see the shape taking place. It’s a circle, nestled neatly in the square plot of land, the edges resting just shy of the squares edges. Inside the circle, the lines cross each other forming angles at every point they touch the circle. 

She wants to say that it looks exotic and beautiful, but the words cannot seem to form in her mind. Guilt, perhaps, a voice whispers deep within, over what she plans to do to Sebastian. Binding him to their family, to this area so that he offers protection for them. Protection from the things that they cannot hope to fight against. And even those that they can. Throughout their life, they made enemies as they grew their empire. Fighting against certain politics make them unpopular in some groups, and jealousy runs rampant throughout human nature. Corporate espionage isn’t unheard of, and Rachel knows that in time, someone will threaten her family directly.

If Sebastian, in all his strength and cunningness, can protect them, then she’s willing to swallow the guilt at moving forward with the plan. Even if the guilt sits in her gut, curdling and rolling until it makes her want to vomit. The thought of her family falling victim to someone who looks to harm them though, makes her sicker still. It forms a physical sickness that she feels throughout her body. Like poison drifting through her veins.

She plans for him to act as their first line of defense, spotting the targets before they set foot on their property. She’s seen him scent out sounds and smells before she could even acknowledge their existence. He’s the ace in her pocket and given his propensity to Ciel, Rachel knows that Sebastian will follow her son to the ends of the earth. Bound to him or not. However, she doesn’t want to play with chance and she’ll take any advantage she can to ensure Sebastian’s loyalty to her son.

Some parents paid extra to tutor their children beyond the schoolyard to guarantee that they exceled in life. Rachel does the same, only she plans additionally to ensure that her child lives so that he can continue to surpass those around him.

Candles adorn the ground, one unlit item at each angle where the lines and circle meet. It sends the unease in Rachel’s body skyrocketing and she examines the feeling in a calm manner. The more she stares at the image – pentagram, her mind corrects, because she cannot deny it anymore that the design imprinted upon the ground resembles a pentagram – the more her mind threatens to have her back out of the plan. Not due to guilt, but out of fear. Magic remains something they haven’t touched. For all that they have a merman living in their lake, he doesn’t practice magic; that they can see. 

This though, has every memory of Sunday morning church rearing to life within her memories. Words of caution against demons, witches, and evil doers. The pentagram looks demonic, and in its ways, it probably is, given what they plan to do to Sebastian. It was one thing to think about enslaving Sebastian, and another thing entirely to follow through. 

Before she can change her mind, Rachel turns from the window and walks out of the room on shaky legs. She can’t let herself regret this now or go back on her promise. Doing so might turn out worse for them, and Rachel refuses to draw the ire of Angela.

She paces throughout the study as she waits for Angela to finish and all too soon, the witch stands at the door. Angela casts a long shadow in the setting sun, and Rachel tries not to feel as though it bodes ill for her.

“I am ready, Mrs. Phantomhive,” Angela says, her hands clasped before her. No traces of chalk remain on her fingers. Instead, they look clean and neatly trimmed. “Whenever you are ready, we can start.” A pause. “I would suggest leaving your child inside for this. I cannot promise that the merman won’t try to escape or harm someone. It’s in our nature to lash out and attack those that cause us pain.”

Rachel nods and has Vincent stay with Ciel as she goes outside, trailing Angela. Ciel doesn’t protest her leaving, completely unaware of what she’s about to do to someone he considers his best friend. 

Outside, the air feels still and almost oppressive as they make their way to the pentagram. Undertaker already stands next to the lakeside, conversing with Sebastian in the merman’s native language. Rachel can see the confusion on Sebastian’s face and crimson eyes flicker between Undertaker, the pentagram, and Rachel. She doesn’t know if he understands what’s about to happen, and she signals Undertaker to grab Sebastian from the water.

To her surprise, Sebastian goes willingly; even though she can see the tension in his shoulders. Undertaker carries him over to the circle before placing him inside on the dirt. “How did you get him to agree?” she asks as Undertaker steps next to her after exiting the circle. “I thought that,” she trailed off.

“That we would have to force him?” he finishes and Rachel nods. “I told him that it would help Ciel and allow them to see each other more often. Plus, he can accompany Ciel when he leaves town this way. He agreed after that. Albeit, he still has his reservations and I might’ve left a few details out.”

Rachel nods, swallowing to settle the discomfort in her gut. Her shoulders straighten as the witch glides over to them on silent feet, a short knife clasped in her hand. She eyes the weapon warily, unsure what Angela tends to do with it and hoping that she can avoid any potential violence if needed.

“For this to work, I need a payment,” Angela says.

“A life for a life?” Undertaker ventures.

The witch shakes her head, short hair brushing lightly against her cheeks. “Not quite so drastic. Blood will finish sealing the deal and imprint the spell. Blood for blood.”

Rachel chews on the inside of her cheek before looking at Undertaker for confirmation. He gives her a short, terse nod and Rachel eyes the knife again. She pulls in a deep breath before holding out her hand. She can’t back out now. Not when everything remains so close within their grasp.

Angela approaches slowly, as though not to frighten her, and presses the blade to the palm of Rachel’s hand. It’s a sharp prick as the tip pierces skin and crimson wells to the surface. Ironic, Rachel thinks, given Sebastian’s color that the payment is blood. She stumbles after the witch as Angela guides her around the pentagram, letting the droplets fall to the ground at each line that crosses the circle.

They finish their circuit and Rachel steps back, cradling her hand to her chest as Angela approaches the pentagram. Her hands raise out over the circle, lighting the candles with magic. “We will begin now,” she says softly.

The pentagram glows purple, a bright color that does nothing to illuminate the night as it rises from the ground. Instead, it seems to cast dark shadows against the ground, bathing the area in darkness. It continues to rise, circling about in the air over Sebastian who still lays flat on his front. His tail curls – similar to that of toes curling with anxiety – and Rachel avoids his searching eyes. Instead, she keeps her gaze locked on the spinning pentagram as it starts to lower.

It drapes itself over Sebastian like a blanket, even though it has no physical form that Rachel can see. For several heartbeats, it stays there as Angela mutters under her breath. In between the next heartbeat and the blink of her eyes, Sebastian screams loud enough that the trees shake around them. Birds take to the sky and ripples appear on the lake’s surface. It’s enough that the hairs on her arms stand on end, and every nerve within her body demands that Rachel run as far as she can.

Sebastian thrashes about on the ground, seizure like and Rachel worries that he’ll snap his back at the way it bends up. The stench of burning flesh fills the air as Sebastian’s fluke _burns_ and _dissolves_ as he lies on the ground, still screaming in pain. The smoldering fire works its way up his tail, searing his flesh and Rachel turns around to throw up at the smell as it hangs pungent in the air.

She keeps her hand pressed to her mouth as she peers at Sebastian’s prone figure from the corner of her eyes. Because she owes it to Sebastian to watch. To know what she put him through for her own selfish desires. Rachel regrets it a moment later as the smoke starts to clear and the fire continues to move up Sebastian’s body, leaving in its wake, bleached white bone.

It’s enough to make her dry heave and it stings that no one offers her comfort. Although if anyone desires the relief, it’s Sebastian. The merman hasn’t moved since the flame burned past where his ankles would be, and Rachel takes small comfort in knowing that at least passed out, Sebastian can’t feel any pain. 

“He’s still awake,” Undertaker says next to her suddenly. She gives him a quick look and he shrugs at her. “Your shoulders relaxed. I assumed what thoughts dwelled on your mind.”

“He’s unconscious,” Rachel argues. Their voices pierce the night air and she wets her lips before continuing in a softer tone. “He’s not moving. He can’t be awake still.”

Undertaker hums. “The pentagram’s magic keeps him from moving. From making a sound. He’s still very much so awake and feeling everything inflicted upon his body.”

Rachel squints at Sebastian’s body, refusing to believe it. A search of his face reveals a wide crimson eye staring back at her. Pain fills Sebastian’s eyes and distorts his features, while a thin line of what looks like vomit trickles from his mouth to puddle underneath his head. Rachel looks away before she can throw up again. 

She looks back again when a loud crack sounds through the air. It continues to trumpet in the air, like wood splintering apart, piece by piece. Sebastian strains against the pentagram and the tendons in his neck stand out against his skin as he cries silently; mouth open in a soundless scream against the ground. Rachel looks around him to where the sound originates, and feels her lips part in shock as the solitary tailbone begins to pull itself part.

The bones twist and stretch as they grow, forming knees and feet in the most grotesque of ways. Next to her, Undertaker wavers on his feet. Sebastian struggles, attempting against all hope to escape but the seal holds tight and begins moving up his body. The lower half looking far too similar to a skeleton on display. The pentagram moves slowly and as it passes over the newly formed leg bones, it starts to grow tendons, ligaments, muscles, and skin. 

Like a 3D printer, Rachel thinks hysterically. 

She silently wills the seal to move faster, so that not just Sebastian can escape the grasp of agony, but her as well. It feels like hours, but is probably only minutes, before the pentagram slithers its way up Sebastian’s arm and comes to a stop just over his hand. It lowers itself to press flush against his skin and Rachel can see the smoke that rises from the back of Sebastian’s hand as it burns itself into the flesh.

Sebastian’s scream pierces the night again, growing in fever before ending abruptly as he slumps forward in the puddle of his own bile. His back heaves for breath and his new legs spasm as residual soreness works its way through his body. 

"It is done,” Angela says. “He is bound to your family until the contract is fulfilled. Blood for blood. It is the price to pay for your protection and his shifts.” She pauses. “He can stay in human form for up to two weeks before he needs to return to his original shape. Any longer will cause prolonged pain. The contracted hand must stay submerged in the lake water for thirty minutes before the shift will take place.”

“Why so detailed?” Undertaker questions.

She sniffs at him. “Because if just water changed him back, you would have a merman on your hands in a sudden thunderstorm. This offers an additional layer of protection. Shifting both to human form and back again.”

Rachel nods in understand, eyes still fixed on Sebastian’s still form. “What does he need now?” she asks, because the guilt crashes into her and she needs a way to ease its strength. And perhaps, to earn Sebastian’s trust.

“For now, he needs to rest. I would recommend somewhere dry and soft. Having him shift back to his original form now, after going through the first shift will likely kill him.” The lit candles snuff out around them, leaving only the dim lights from the house behind them. In the dark, Angela’s eyes seem to glow. “Thank you, for your hospitality.”

She disappears after that into the shadows of the night, leaving them to deal with an unconscious merman and eventual, Ciel’s horrified yowls when he realizes what they did to his friend. Blood for blood, Angela said. In the end, Rachel thinks it was worth the cost. 

「It’s not until later that Rachel and Undertaker learn the true reason as to why Angela agreed to bind Sebastian when every other witch turned them down. It turns out that Rachel’s connection to the pale purple merman wasn’t off target. The purple, Undertaker tells her one day while everyone else is outside, giving them privacy, runs in the family. Stepsiblings, he clarifies. Same mother, different sires, but still blood related and still close. By the time they discover this, Angela vanishes to the mountains and remains untouchable to Sebastian’s wrath. 」

**.:|On Water’s Edge|:.**

Water lapped against the outer walls of the boathouse, creating a steady and calming white noise as Ciel relaxed further into his bed. His eyes burned with exhaustion after staring at a computer for most of the day and sitting through back-to-back meetings in the late afternoon. It wasn’t how he wanted to spend his Friday – stuck at the office while Sebastian flittered about freely in the water without him, but what employee actually wanted to work on Fridays? – but the economics of the world demanded that he work.

Work paid the bills and ensured that Ciel continued to live in comfort in his house next to the lake. He clicked his tongue at the thought and rolled onto his side, staring out over the edge of mezzanine. That wasn’t true, necessarily. His parent’s companies left more than enough in the bank for Ciel to enjoy a life without work. Live the life of a jet setter and travel the world without any regard to the people around him as he sipped expensive drinks and stayed in the finest of hotels the world had to offer. 

Yet the thought of letting someone else run those companies while he touted his way around the world made his stomach churn with nausea. They remained a connection with his parents and Ciel refused to let someone else carry their names while he still lived and breathed. Pretty rich boy scared to get dirt under his nails, spoiled and pampered his whole life; came the whispered words when he stepped into the role of CEO those many years back.

Ciel snorted at the thought. Let them think what they wanted. The growing numbers spoke for themselves and in the end, the higher closing quarters proved enough to silence wagging tongues. The sweeping company wide changes he implemented made for enemies, but it also made for better profits and employee loyalty. If a couple board members felt hurt over the new policies and threatened to quit, it wasn’t skin off Ciel’s nose. Better to surround yourself with people in line with your morals than those that would rather stab you in the back the moment a chance presented itself.

He shifted over onto his back again, the covers rustling under his body. A sigh and Ciel burrowed deeper into the covers. If he strained his ears hard enough, he thought he could make out the sound of Sebastian depositing various trinkets along the wooden deck of the boatshed. Shells and polished stones that glittered under the sunlight come morning. A merman’s way of courting and showing devotion.

He shook his head on the pillow in fond exasperation and closed his eyes, letting the sound of water lull him to sleep. Wood creaked as the shed settled in the water before everything fell quiet. Ciel yawned and relaxed more into the bed, allowing the tendrils of sleep to carry him off into a waiting dreamland. 

In the distance, he could vaguely make out Sebastian moving about in the water. A soft tapping against the wood, followed by a heavier _thump_ of a larger item setting down against the deck. No doubt, Ciel would have a mess to clean up in the morning, sorting through the various shells and rocks.

The noise sounded again and Ciel’s eyes snapped open. His heart pounded loud in his chest, threatening to drown out the sound below on the deck level. Sebastian never made a sound unless he wanted to. He move silently, a predator in the water. 

Ciel pushed the covers back as quietly as possible and swung his legs over the edge of the bed. With soft feet, he padded over to the edge of the half wall and peered over the edge. The mezzanine overlooked the lower deck; a small kitchen and living area tucked just underneath the loft, while three boat docks stretched out into view. Two of the docks currently held the family boat and other watercraft, while the third remained empty. Ciel’s eyes scanned the area around the empty bay, searching the wooden floor for any signs of water or miscellaneous trinkets. 

He scowled into the dark as the noise sounded again, annoyed with himself for letting someone else get the better of him. A heavy noise echoed across the lower deck, followed by a muffled curse before the side door swung open slowly.

Illumination from a flashlight swept across the wooden deck and Ciel pressed himself closer to the wall, flattening his body as best he could. Nothing much of value resided in the boatshed; only outdoor furniture, some cooking appliances, and the boats themselves. Easily replaced if stolen, and Ciel didn’t put much worry in losing them. 

What concerned him more was the question of why someone would chose to break into a boatshed, when the true valuables resided within the main house. Unless the thief was a boat enthusiast, then they came for something else and Ciel’s heart seized at the thought. 

Not for his safety, but Sebastian’s. 

Ciel doubted the robber even knew that Ciel slept in the boatshed tonight and more than likely, they were after the merman. A poacher or someone incredibly stupid. Only a select few knew of Sebastian’s true form – Ciel could count the people on one hand, including his parents and himself – and the thought nearly made Ciel laugh. Surely his parents hadn’t told anyone of the merman, leaving two other individuals; one of which wouldn’t say anything either.

That only left Undertaker.

He poked his head back up to see over the rail as the person’s footsteps quieted. In the dark, Ciel could make out the figure’s shadow standing just near the edge of the open dock. The flashlight shone into the water, flickering about the still surface. The light bounced off something reflective, and from where he sat, Ciel saw the brief shine of red before it vanished once more. 

Too fast to make anything of it, and Ciel settled down to wait, knowing tonight would end one of two ways. Either Sebastian would act coy and playful, teasing the person with mere glimpses of what they thought to exist in the depths. Or he would remain out of sight, and the thief would never know that he lurked just below the surface. 

Either way, the person sealed their fate the moment they stepped unwelcomed into Sebastian’s domain.

The water rippled as several bubbles rose and popped against the surface, and a moment later, Ciel could make out Sebastian’s body approaching the surface. The flashlight jerked briefly before steadying, and when the beam found the water again, Sebastian’s head poked just out of the water. Ears trembled and crimson eyes shone in the light, pupils blown wide.

“Wow,” the person breathed and took a step closer to the edge. “Look at you.”

Sebastian ducked his head and dipped below the water again. His fluke crested the water, pale red in its thinner spots, and fragile looking, like that of a fish. 

“No wait,” the person called, voice echoing around the room. They reached into their bag and pulled out a fish, dangling it over the water. Ciel clamped a hand over his mouth to keep from bursting into laughter. 

Seconds passed before the water rippled again as Sebastian appeared, eyes glued to the fish just overhead. He chirped and whistled low in his chest in obvious want of the food – even though Ciel knew that Sebastian ate more than enough and after the recent dinner they had, couldn’t be anywhere near starving like he portrayed.

“Yeah, there you go,” the man said and squatted down. Sebastian shied away at first but the allure of the fish grew too strong, calling him back closer. “That’s it. Take the fish you stupid creature.”

Sebastian snatched the fish from the man’s hands and arched back into the water, long tail breaking the surface this time. The man swore, no doubt taking in the length of the tail and guessing Sebastian’s age from it. Sebastian wasn’t a fledgling merman, and merman flesh sold by the pound. With his weight and height, Sebastian would fetch a hefty profit once sold.

Ciel’s eyes flickered to the second boat dock as a pale hand poked out of the water. He watched as Sebastian set the fish to the side, tucking it neatly between the wall and a supply shelf before vanishing under the water again. 

Drugged then, he surmised. Not an amateur poacher.

“Come on fishy,” the poacher coaxed, drawing out a second fish. Sebastian broke the surface again, tongue coming out to lick at his lips as he reached for the fish. The man gave it to him, and Sebastian repeated his act of submerging below the surface to eat. “There we go, almost there.”

The man reached into his bag, pulling out a restraining snare, similar to that of a dog-catching pole, and a long needle. He set them to the side, out of sight but within easy enough reach that he wouldn’t have trouble grabbing them. Once done, he rooted around the bag for another fish, this one large and plump. A salmon, by the looks of it. 

Sebastian breached the surface again, his eyes narrowed in on the fish in the man’s hand. He whistled as he reached for the fish, only to have it pulled back out of his grasp. Eyebrows furrowed at the man, clearly not happy at the teasing but drifted closer. The allure of sinking his teeth into something larger and more filling driving his motions. 

He stretched out for the fish again, reaching until his chest bumped against the edge of the dock. Sebastian glanced down briefly at the wooden surface, seeming almost surprised by it, and then whistled in shock as the snare circled around his torso, pinning his arms to his body.

The poacher grinned. “Yeah, I knew you couldn’t resist that one. Greedy little beast. But you’re not so little are you,” he cooed, keeping a firm grip on the pole even as Sebastian tried to escape. He thrashed about, spilling water across the surface of the desk as his movements grew more frantic. “Oh fight all you want. It won’t take long before the sedative in those fish takes place. Then you’re all mine. And with your build, you’ll be well worth the effort of catching you. With the price you’ll fetch, I can make a fortune.”

Sebastian snarled at him, showing pointed teeth, and ears flattening down against the sides of his skull. He struggled more, twisting and squirming in an effort to break free, but the snare cable held tight. It cut into pale skin, sending blood trickling down Sebastian’s chest and into the water.

Minutes passed before the thrashing slowed and Sebastian panted for breath. Ciel clutched the edge of the railing as the poacher approached him, malicious intent filling each step. He reached down and grasped Sebastian by the back of his neck, hoisting him up from the water like a doll. 

“Look at you. Weak and pathetic, cowering under my heel as you should,” he murmured. Fingers traced over Sebastian’s face, pinching the skin as he moved down the merman’s body. “Good build, nicely muscled. Still in your prime. Maybe I should sell you to a breeder.”

Sebastian blinked sluggishly at the man, eyelashes ghosting across pale cheeks. He wiggled about weakly before settling limp in the poacher’s grasp.

“We’ll let the money decide what happens to you,” the man said, lowering his arm so that Sebastian sunk back into the water up to his chest. He reached behind him to grab the needle – a heavier sedative, if Ciel had to guess – all the while, keeping his attention on the merman.

Fingers closed around the needle at the same time Sebastian pushed away from the dock with a strong undulation of his body. Water crashed across the deck, soaking the surface. Another kick jerked the pole from the poacher’s hands and Sebastian vanished under the water a second later. 

Angry waves lapped against the sides of the dock from Sebastian’s departure. They filled the air with their aggressive sounds, barely covering up the furious curses that left the poacher’s mouth. He spat in the water’s direction as it started to calm and in between his next breath to curse Sebastian, hands shot out from the water’s surface. They grasped the poacher’s ankles and before he could even scream, dragged him into the lake.

Ciel hummed and stood up from his spot. With easy motions, he reached for his jacket at the foot of his bed and slipped it on. Barefoot, he padded down the steps and leisurely made his way to the open boat dock; mindful of the puddles of water that still covered the deck.

The water’s surface broke as a figure emerged, frantic and gasping for breath. Wild eyes flickered about, searching for the nearest dry spot before making his way towards it. Hands just grasped the edge of the desk before Sebastian leapt out of the water and tackled the poacher, pushing him under the surface once more in a burst of bubbles.

The lake churned in his absence, as though it fed off Sebastian’s anger. At times, Ciel wondered if Sebastian had control over the watery element. He dismissed the thought as soon as it came to mind. The less he knew the better in some ways. Shaking his head, Ciel moved to the side of the deck where they kept a rescue hook mounted on the wall – just in case. Safety first, after all.

He blinked as Sebastian let the poacher go again, allowing him to surface and suck in air desperately. “Help me!” the man gasped, spotting Ciel as he struggled for land. “Please help me.”

Water rippled as Sebastian swam around him, akin to a shark circling their prey. It drew a terrified whimper from the man and his pleas grew more frantic as Sebastian cut him off again from the dock. 

“Please!”

Ciel leaned his head against the pole as Sebastian continued his circling. “Sebastian,” he called, knowing all too well that the merman could hear him underwater. “Finish your game so I can go back to bed. But please, no blood on the deck this time.”

The poacher choked on a mixture of water and air; the last breath he would ever take. A heartbeat passed as Sebastian surged forward, mouth clamping around the man’s neck as he pushed them down under the water. Bubbles gurgled to the surface, breaking into large ripples that eventually tapered out and vanished against the docks sides.

“That was cruel,” an amused voice said behind him and Ciel spun around to see a familiar figure sitting at his – or rather Sebastian’s – table. “You could’ve saved him.”

“Undertaker,” Ciel responded. He looked at the rescue pole and then dropped it to the floor with a shrug. “I suppose I have you to thank for leading a poacher to our doorstep?”

The man giggled. “Sebastian and I have an agreement, as you know. One you agreed to as well,” he said. “Plus, it ensures that your merman has the correct diet.”

“Warning would’ve been nice,” Ciel sniffed.

“I told Sebastian earlier this afternoon. You were at work, I believe he said.”

Ciel rolled his eyes. Of course, Sebastian wouldn’t tell him. Part of the fun came in the surprise. So long as the man didn’t endanger Ciel or the rest of their pod, Sebastian would draw out the torture until he grew bored.

He grabbed a squeegee blade and a few towels, intent on cleaning up the area while he waited for Sebastian to return home. He didn’t ask Undertaker who the man was. Ignorance was bliss, and the less Ciel knew, the better. The one thing he did know was that Undertaker only lured unsavory individuals to Sebastian’s lake for their watery death. Murders, rapists, and on the occasion, poachers who threatened the magical community that Sebastian considered his extended family. Ciel didn’t take their murders lightly, but he also didn’t lose sleep over them either.

“He’s doing well?” Undertaker asked as Ciel pushed the excess water back into the lake.

Ciel nodded. “Yeah. His shifts aren’t any easier, but he seems happy,” he said. “I mean, he stays here, at least.”

Undertaker hummed but didn’t say anything else and Ciel didn’t push for conversation. The man might’ve gone along Rachel’s plan all those years back, but it didn’t mean he liked the results. Like chaining a bird to the ground, he once commented to Ciel several years after he helped burn the pentagram into Sebastian’s hand. Ciel couldn’t help but wonder now if he regretted his actions, knowing the outcome now.

The water rippled as Sebastian circled the area with an easy flick of his tail before surfacing, dragging Ciel from his thoughts. He looked up at the merman and frowned. “Really?” he asked, in reference to the severed arm clamped in Sebastian’s jaw.

“Yes,” Sebastian answered simply.

Ciel shook his head fondly and set the squeegee to the side before shaking out a towel. He settled on the floor, eyes raking over Sebastian’s features for any additional injuries. None appeared to his trained eye; although it proved hard to see any wounds as Sebastian continued to tear into the arm, blood spilling down his chest from his meal. 

“You’re okay?”

Sebastian nodded. “I am fine. In the end, he was not a threat. He laced the fish and I could smell the herb when I surfaced. He was fun to play with though. He begged so nicely until the end.”

"Why play around with him?” Ciel asked, unable to help himself. An answer sat in the back of his mind, but the yearning to see it clarified pushed him forward. “You have other manners of enticing your targets.”

Blood painted sharp teeth crimson as Sebastian grinned widely. “Where is the fun in that?”

The radius – or maybe ulna, Ciel couldn’t tell from where he sat - bone crunched under Sebastian’s teeth as he continued to strip the flesh, sucking the very marrow from deep within the bone. Come morning, not a trace of the poacher would remain. All evidence vanished down Sebastian’s gullet. 

The perfect killing machine and protector. Just as Rachel intended.


	3. Chapter 3

**Notes for the Chapter:**

> Warnings for violence and minor character death

**.:|On Water’s Edge|:.**

「Sebastian protects his pod like this:」

The first time the Phantomhive family witnesses Sebastian’s thrall at full strength and power, it’s in the middle of a quiet night. He hears the approach of the heavy van before its wheels even make the gated entrance; the weight of the vehicle reverberating along the road so that ripples form at the very edges of the lake. They alert Sebastian that something isn’t right and the very water trembles with his irritation. 

He circles the lake in fast laps, tracking the vans path as it travels past the gate and continues along the fence line. There, it stops and the engine idles for several long minutes. He watches from a distance as heavily clothed figures exit the vehicle and proceed to gain entrance through the metal fence. They use fire, something Sebastian knows about but doesn’t. He knows that it can hurt and Ciel tells him it’s dangerous, and the thought of someone using fire so close to his domain makes his ears tremble in anger. His tail threatens to slap against the lake water in aggravation, but he quells the urge last minute. 

These figures aren’t merfolk. Sounding a battle cry or making threatening gestures won’t work for them. Somewhere, in the back of his mind – the part that’s now enhanced more due to the witch’s work – he knows that this fight will require something else. Finesse, the word comes to mind; sounding like Vincent’s voice once while they listened in on a meeting, months ago.

The fence falls to the ground with a loud crash, and the lake goes still, along with the rest of the land. Creatures know that stepping uninvited into another creatures land – or water – risks a challenge. These figures though aren’t creatures. They’re human through and through, and they enter into his area without care. Heavy boots trample the grass as they start their way to the house where his pod – his weird, two-legged pod that can barely hold their breath underwater and think splashing about in the water constitutes as swimming – lay sleeping. 

Sebastian’s skin vibrates with energy and he submerges into the water again. He follows the figures path alongside the lake as they make steady progress to the house. He knows the house has an alarm system. Something akin to magical barriers, but instead of magic, runs on technology. He doesn’t trust the system, crinkling his nose at the panel in the wall when Ciel first showed it to him. He’s still unsure how a simple thing on the wall can offer protection when it doesn’t emit any magical energy; only electricity. It doesn’t seem crafty enough.

Yet Ciel insists that the system provides enough protection. Sebastian snorts at the thought, bubbles erupting from his mouth in a violent manner and floating to the surface in a slow motion. And humans called his actions and thoughts strange.

He shakes his head and circles the dock twice, dipping in and out of the shadows as the humans gather near a wall of the house. Another box mounts itself to the wall there, and from where Sebastian swims, he can see the humans messing with it. It has something to do with power and electricity, he vaguely remembers. His pod remained insistent that he never touch the device with wet hands because it would kill him.

Electricity. Similar to that of the jellyfish that swam in the ocean so far away. As a fresh water merman, Sebastian has only heard stories of the creatures that live in the salty waters of the oceans. They sound fascinating and he longs to see on up close, but his skin can’t stand the high concentration of the ocean long enough to spot one. In some ways, it makes Sebastian envious of the saltwater mermen that reside in the ocean. Their territory much larger and less threatened by the humans. Yet saltwater merfolk out populated their fresh water relatives, and competition between pods happened frequently. Not to mention the higher rates of poaching.

His lips curl at the thought, teeth threatening to dig into the soft flesh of his mouth. Poachers, it seemed, existed for not just creatures but for humans as well. 

Sebastian pulls himself to the surface, lingering just at the edge of the dock as the humans continue their work. A spark erupts from within the box before the ground lights flicker out and the hum of electricity cuts from the air. Around the lake, the surroundings stand in such stillness that for the first time since humans built their coves in his domain, Sebastian can feel the ley lines lurking underneath the earth. Strong and untampered by human meddling. 

For several long minutes, Sebastian reveals in the feeling. Feeding off the earth’s natural energy and that of the magic that infuses within the air. He feels it down to the very core of his body; into the depths of his bones. It feels like coming home – something he hasn’t felt since his birth nearly a century ago – and it makes Sebastian yearn to dive to the depths of the lake and burrow within the silt. Encasing himself in the earth’s pulse and embrace.

He fights the urge and stays above the surface, continually watching the humans. He knows not what they intend; only that it doesn’t bode well for his new pod. He can sense their hostility in the air and read it in their posture. They’re like an aggressive and posturing minotaur. No sense of smarts in their heads, but their bulk and strength make them dangerous. Common sense and negotiating won’t work. Reasoning with someone – or something – intent on attacking doesn’t work; Sebastian knows that all too well. Yet still, he holds tightly to the pier and refuses to move until he knows for sure that the humans intend harm to his pod.

Sebastian knows his orders from Rachel. She drilled it into his head the moment human feet took place of his fluke. He’s not to defend until he knows for certainty that someone poses a threat. Humans took death of their kind seriously, and taking a life would bring unnecessary burdens to the pod. Therefore, despite instinct that demands Sebastian sink his teeth into their flesh, he holds back. 

He watches as they cluster around each other, talking in hushed tones that don’t reach Sebastian’s sensitive ears. In the darkened night though, they rummage through a bag near their feet and finally pull out black objects that look like heavy shadows in the night. They’re large but fit within their hands, some the length of Sebastian’s arm, thick at one end and tapering to a thin point at the front.

A figure breaks from the group and kneels in front of the door. Heartbeats pass before the door swings open and the group moves forward in a quick, steady precession. They keep the shadowed objects up near their face, peering down the long, thin front part of the object. Sebastian growls low in his chest, the sound vibrating the water around him.

If Rachel lectured him enough on the importance of not killing until necessary, then she browbeat the images of different weapons into his mind. Sebastian didn’t bother telling her that he already knew most of them – or at least varieties of them. Humans, for all that they prided themselves on evolving rarely strayed far from the small comfortable circle they backed themselves into. A knife was a knife, and a gun was a gun. No matter how the humans changed its look or firepower, and Sebastian saw enough of them through his lifetime to recognize their shape without Rachel shoving the information down his throat.

The thought to let the poachers complete their job and wipe out his pod never crosses his mind. He hefts himself up onto the dock, bracing his palms on the smooth wood so that only the lower half of his tail remains submerged and calls forth the magic that coils deep within his chest. It vibrates, feeding off the energy that rests heavily in the air after the humans turned off the electricity. The air makes his magic stronger, increases the potency so that the very air around the lake grows saturated with the notes when he opens his mouth and _sings_.

The various frequencies carry themselves along the electric currents in the air, fed by magic so that when Sebastian opens his eyes again, he can _see_ the frequency waves bending to his will. They distort the air around him, rising and pitching in waves so much so that they crest above the towering cove in the distance and still have enough force to dip below the surface of the ground. 

He pulls in another breath, increasing the power behind the words he sings. Sebastian knows that the humans don’t understand the words; only that they hear the melody and sound he makes. To them, it sounds like a high-pitched hum, like electricity vibrating nearby, but soft and smooth, like rolling thunder in the distance and the crash of waves against the lands surface. Undertaker once tried to explain it, but words fail more often than not. A merman’s thrall sounds unique to each human that hears it, and each merman sings a different thrall. They vary in pitch and fever, similar to the way that a mating call can never quite mimic another one. 

Unique, beautiful, and so very deadly.

Sebastian rolls his body into the song, tilting his head up and exposing his throat where the vibrations of his music rests the strongest. The air _shudders_ around him and Sebastian feels the lake ripple around where he dangles in the water. The few other merfolk that populate the outer reaches scatter to the farthest reaches of the lake, desperately seeking to escape his wrath. They can tell that his turbulence comes from one central spot – towards the figures inside his pod’s cove – and that he targets only them. Still, no one wants to risk having that same vexation turned upon them.

The waves of his song pierce the structure, strong enough that they crack the outer walls in their entry. Not enough to damage the structure, but enough that the destruction remains visible. They sweep throughout the house, encircling his victims and his targets. He can feel the moment his song ensnarls them; gripping each individual tightly in its grasp so that everyone freezes in place. Guns clatter to the ground and slowly – too slow for Sebastian’s taste – they start back towards the lake.

Like marching soldiers to a fife, they trek to his tune. Even from his spot in the lake, Sebastian can pin point which footsteps belong to the poachers and to his pod. The racket of heavy boots against wooden floors compared to the soft, barely there steps of bare feet. Together, they make their way downstairs and outside the cove, the poachers leading the pack. 

Their eyes glaze over, pupils blown wide as though they stared into the light of a full moon, and they walk without care. Shoulders low and fingers relaxed at their sides. They have no concern in the world. As the song wraps about tighter in their minds, it weaves deep within their brains; changing the very wavelength of the neurons firing between cells. 

Sebastian changes the pitch, lowering it to something deep and thrumming – and pointedly ignores the pain that starts to build at the base of his throat. Before, his song sought his enemies. Now that he has them within his grasp, he coaxes them closer. The song changes, akin to war drums beating throughout the land. It vibrates within his chest until his body trembles in response.

The poachers draw closer but his pod stutters to a stop near the entrance of the house. With the difference in pitch, his song no longer reaches them as they trail the poachers. Sebastian sees them usher Ciel back inside, Vincent going to call the authorities. Rachel, however, stays where she stopped. A faint shake of her head makes him snarl at her, and he drops his body back into the water.

He swims out further from the dock as the poachers gather on the wooden surface. Instinct thrums within him to drown his victims. To make them pay for what they wanted to do. They threatened his pod and encroached on his territory. Sebastian has every right to take what belongs to him. The poachers stand so helpless on the dock’s surface that he could destroy them easily. No one would find them.

Thought in mind, he pitches his song once more and lets the notes carry through the air one final time. With the sound lingering and the poachers still in a daze, Sebastian dives below the surface. The water welcomes him back home and Sebastian feeds off its energy. Short, fast, and strong kicks propel him forward as he approaches the dock. He shoots out of the water in a blur, tackling one of the poachers into the water. 

Nails pierce her skin easily, slicing through muscle and tendons in her shoulder so that even with medical aid, it will never recover the same way. He lets her surface, screaming her pain and pooling blood across the lakes surface before attacking his next victim. This time, choosing to drag the nearest target off the edge of the dock unseen. The man loses an eye – which Sebastian swallows whole without regret – and bloodies up his leg so that the flesh lays in strips as it peels away from muscle.

By the time Sebastian has his third target in hand, the poachers no longer stand terrified on the dock. Instead, they run frantically to their car. Two of them helping his second victim out of the water, while another supports the first. Sebastian lets them go, already hearing police sirens in the distance. The authorities will catch them before they get past the road and it leaves Sebastian to deal with his final victim.

His hand circles the man’s neck and pushes him deep under the water. Together, they dive into the depths of the lake, the man clawing at his arm in an attempt to escape. Sebastian smiles at him and lets him go once they reach an appropriate depth. The poacher makes his way to the surface, Sebastian right at his heels. He allows the man a quick breath before dragging him under once more. Like a cat playing with its food, they repeat the motions. Sebastian allowing him more breath sometimes and other times, barely any so that his movements turn sluggish.

The sixth time they surface this way, he hears his name called in a sharp sound. He turns to find Rachel standing on the dock, face pale. Sebastian’s lips pull back in a snarl at her – not because he doesn’t recognize her as a member from his pod, but because she attempts to stop him – lost in the bloodlust of a kill and before she can tell him to stop, his hand pushes its way through the man’s chest. Bones crack and muscles tear as Sebastian digs out his heart. He bites deep into it and dives back under before Rachel can say anything; leaving the humans to determine how best to clean up the mess.

「He later learns that Rachel tells the police that Vincent shot the man as he attempted to escape. The police accept the story, given all the weapons around the house. They claim self-protection and given the evidence against the poacher, the case closes quickly. Rachel never comments about the slip, keeping secret the true strength of Sebastian. Just as Sebastian never comments on the way she tried to bring him to heel. Somethings retain their wildness, despite all the training. 

The police catch the remaining poachers and Sebastian learns that none of them can explain what happened while down at the lake. Later, they concoct the story that Sebastian – human Sebastian, that is – fought them to protect the house. The loyal family butler doing all he could to protect his family. It’s not the truth, but it’s not a lie either. When asked, Sebastian simply answers with: “I’m just one hell of a butler.” 」

**.:|On Water’s Edge|:.**

Ciel smiled at the man standing across from him, hoping to put him at ease as the man’s fingers fidgeted about over the back of a plush chair. A tower could fall to ruin if it didn’t have a strong base, and Ciel purposely sought the weakest link in this mole hunt. Sebastian protested that it wasn’t near as fun to go after the weaker fish in the pond, but Ciel didn’t need his main target knowing that they were onto him. Especially when at this point, it was all speculation.

The man shifted again and Ciel watched as he brought his hand up to wipe at his mouth – clearing off the sweat beading up along his upper lip. Ciel smiled again. “Kelvin, thank you for again for meeting with me like this.”

Kelvin flashed a tight smile back in return. “I’m honestly surprised that you even know of me Mr. Phantomhive. I’m just a lowly mail room man. I don’t even deliver the mail.”

Ciel waived a hand. “Nonsense, I know of all the employees that work for me. From the lowest floors, all the way up to the top. Large gears can’t operate a vehicle alone,” he said and leaned against a nearby table. “The smallest gears perform some of the most important work throughout the whole car. Without it, the larger gears would grind to a halt and the machine stops working. Everyone, large or small, has an importance to the company.”

“I, thank you, sir,” Kelvin said, a flush working up high on his cheeks. “I never thought about it that way, if I’m honest. I know it’s not glamorous, but it pays the bills.”

He nodded. “Despite its quiet nature, do you enjoy your job?” Ciel asked. Kelvin stiffened and Ciel raised his hands to put him at ease. “I mean no threat. I use this time at the company picnics to speak with random individuals to see their perspective on the company. Things they enjoy and things that could change. Within reason of course. I’m sure you’re aware that I value my employee’s happiness.”

Kelvin relaxed slightly and gave a small incline of his head. “Yes sir. The benefits you offer allowed me to take paid time away from the company when my wife had a baby. I can’t get that at many other places. And the chance to place our child in day care here saves so much for us.” He paused as though to collect himself. “I’m truly grateful for all that provide for us.”

A warm feeling of relief unfurled in Ciel’s chest at the words. Even though he had Kelvin cornered without his knowledge, it still brought him comfort to know that he provided enough opportunities for his employees. Hearing the horror stories of how other companies operated chilled his blood and Ciel spent countless years fighting for a change in his offices to ensure they set a gold standard. 

It made enemies and others scoffed at his seemingly naïve ambitions, but their turnover rate spoke for itself and the recruiting offices rarely had trouble filling empty positions. And for the enemies that he did make, Sebastian offered more than enough protection.

“That’s good,” Ciel said honestly as the side door to the office opened. “I’m glad to hear that you can use the company benefits to your advantage and that they help you so much.” A pause. “Would you like something to eat?” he asked as Sebastian entered, pushing a small cart in front of him.

“They’re still warm from the oven. Please be careful when picking them up,” Sebastian said softly.

Ciel’s eyes flickered over Sebastian’s form, taking in the neatly fitted black suit and tie. The merman detested the tie, saying it felt like a noose, and he complained that the shirt collar itched his neck. For now, Sebastian appeared to take the discomfort in stride and without complaint. Yet Ciel knew that once Sebastian finished his role, Ciel would find the clothes rumpled in a heap at the foot of his bed while the merman submerged himself in the bathtub. 

He rolled his eyes at the thought and reached for a cookie on top of the pile. It pulled apart easily, revealing a gooey warm center and melted chocolate. “Please, try one,” Ciel said, taking a bit. “Sebastian makes the best desserts. I’ve tried to learn his secrets, but he remains persistent.”

Kelvin laughed. “My sister is the same way. She makes this three-layer cake where each layer is a different flavor, but they all meld together on the tongue. I have no idea how she does it.”

“Really?” Sebastian asked. Ciel could almost see his ears flicking forward. “That sounds similar to a dish that I tried once. I could never get the different flavors just right, much to my disappointment.”

Ciel cleared his throat before Sebastian could get too caught up in his excitement. The last thing he needed was the merman focused on the wrong subject. Sebastian grumbled under his breath but offered his apology before stepping to the side of the room, busying himself with cleaning up the mess on the desk.

“If you get him started on cooking or baking, he’ll never stop,” Ciel said as Kelvin reached for a cookie. “As I said earlier, I’m grateful for your honesty in the things that you enjoy with the company. Can you think of something that we could improve on or offer that we don’t currently have in our benefits?”

Kelvin swallowed and brushed cookie crumbs off his fingers. “I’m not sure,” he started and fiddled with the fabric of his pants. 

Ciel watched him carefully, taking in the expressions that flickered across his face. Each one wanting to tell a story but lacking the medium to do so. He reached up to rub his ears, one at a time, before crossing his hands together in front of him. “Nothing at all?” he pressed. Kelvin looked at him and Ciel’s smile tightened. “Because I think you do. Why else would you conspire against me if you wanted for not?”

“I’m sorry?” Kelvin said, eyes widening just so.

“You listed all these reasons that you enjoyed working for Funtom Works, but what I can’t understand is why you would risk everything good that we have to offer for someone else,” Ciel said. Behind him, Sebastian circled around the desk. “You must want something or have something against me.”

Kelvin shook his head. “I don’t know what you’re talking about, Mr. Phantomhive. I work only for you.”

Ciel pulled himself up to sit on the desk, feet dangling just inches from the floor. “Tell me,” he demanded. His arms crossed over his chest, head inclining back just so. “Tell me your desires and secrets.”

The room thrummed with energy, as though someone turned on an electric current nearby. It resonated throughout Ciel’s body, starting with his head and moving down to his toes, so that he couldn’t help the fine shiver that shook his body. His hand shifted back on the desk, bumping into Sebastian’s fingers and he gave them a brief squeeze before standing up again.

“Tell me,” he hissed.

Kelvin’s shoulders slumped and he relaxed into a nearby chair as the vibrations increased. For several long moments, his eyes struggled to focus, eyelids drooping as though fighting off sleep. “I didn’t want to, but he promised me money. Said he could give me enough to put my daughter through college if I could do what he asked,” he slurred finally. Sebastian prowled towards the chair and the pulsations rocketed. “I wouldn’t have done it otherwise. I like my job, but it doesn’t pay enough to put my child through school. I have other debts.”

“Gambling?” Ciel pressed. Kelvin nodded, sluggish in nature and his eyelids fluttered shut. His head lolled and his eyes opened as Ciel started to speak again. “He knew your weakness then. Knew where to hit you the hardest. What did he tell you to do?”

Kelvin eyes flickered shut as Sebastian cleared away the tray of cookies in front of him. From where he stood, Ciel could see the merman’s throat vibrating, humming out a low tune that coaxed his victim into submission. Turning him into putty in his hands. The song, though it lacked words to the human ear, proved powerful. Sebastian pitched the tone low, barely discernable to anyone within a few feet from him, so that it delved deep into the conscious mind and pulled out the information sought. It loosened lips and lowered inhibitions in ways that alcohol couldn’t, and Ciel never saw a more powerful weapon that what Sebastian wielded. 

“He wanted me to divert some packages and blueprints to his office before they reached R&D,” Kelvin murmured.

“Why?”

A shrug. “He needed to make copies, I think. Make copies and improve on them so he could make his own products. He said he had buyers already.” A pause for three slow heartbeats and then; “He intends to start his own company and take you out of competition.”

Ciel hummed and shared a look with Sebastian. It confirmed what they knew already and helped fill in the missing information that they still sought. Before they could take down the mole though, they needed to know how far its arms stretched and who controlled the tower. Ciel ran a hand through his hair and nodded to Sebastian, letting him know that he could continue. They ran on a tight schedule. Knowing that taking too long could draw suspicion, but more than that, risked harming Sebastian.

The thrall, when used for protection or for rooting out information, wasn’t meant for extended periods of time. Anything longer than ten minutes ran the risk of damaging the vocal cords. Already, Ciel could see a bead of a sweat trickling down Sebastian’s face as he increased the vibrations of the thrall while Ciel asked his question.

“I don’t know,” Kelvin answered. “He didn’t tell me everything. Claimed it was for my safety. But I know he has some people in finance skimming the books to help start the business.”

Ciel’s lips curled at the answer and he forced himself to focus. “Tell me who your handler is. Tell me so he can’t keep harming you,” he said instead. Play the sympathy and helping card. It softened the pitch of the voice and increased the chances of the target giving more information. 

For several long seconds, Kelvin stayed quiet. His eyes stared unfocused at Ciel as his conscience tried to beat back the thrall. Hesitation shone on his face and Sebastian circled the chair like a shark, drawing to a stop behind him. His hands rested on the top of the chair as he leaned forward, placing his face right next to Kelvin’s head. Ciel shuddered as the room _vibrated_ under Sebastian’s thrall, sending water in a nearby cup rippling with the force of it.

“Mr. Viscount,” Kelvin said. “He’s the one that approached me. He has secrets on everyone.”

“Sebastian,” Ciel murmured and the thrumming ceased in the room. He reached up to rub at his ears, pulling out the chunks of bee’s wax he pushed in them earlier. He shook his head as sound filtered back into his senses and set the wax aside. “Thank you.”

“You were not affected?” Sebastian rasped. His breath came labored, sweat dampening his face and around the collar of his shirt. It made Ciel reach out for the merman, wiping away the beads of sweat that curved down Sebastian’s cheek. 

Ciel shook his head. “No. The wax does its job. I’m starting to wonder if Homer’s tale wasn’t so much a tale anymore,” he said. “How are you? You sound horrible.”

Sebastian gave a small shrug of his shoulders. “I have suffered through worse.”

“That isn’t comforting,” Ciel stated, knowing all too well that nothing could beat the night Angela and Rachel placed on him. “After this, have Tanaka make you some hot tea with honey, it should help.”

“It can wait,” Sebastian started.

“Now, Sebastian,” Ciel pressed. His fingers trailed through damp locks, then back to cup Sebastian’s cheek. “I hate to see you in pain like this.”

Sebastian made a displeased noise. “But the plan.”

Ciel drew the merman closer, dropping a quick, sweet kiss to trembling lips. “We will proceed as planned. But not until you’ve healed. Your health and wellbeing means more to me than capturing our target.” His hand fell away, fingers skimming over soft skin before dropping back into his lap. “Let’s go wake him. We have more hunting to do.”

Sebastian crouched down in front of Kelvin and shook his shoulder carefully while Ciel called his name. Eyelids fluttered open and puzzlement flickered over Kelvin’s face. “What happened?” he slurred.

“You got a little light headed there for a bit and had a fainting spell on us,” Ciel explained. “Did you drink enough water while outside? The summers get particularly hot here and if you’re not careful, you’ll fall victim to dehydration before you know it.”

He shook his head. “I’m sorry sir; I’ve never done that before.”

Ciel waved a hand. “It’s fine. Sebastian can you take Mr. Kelvin to one of the spare rooms so he lie down for a bit? And bring him some water as well.”

“Yes, sir,” Sebastian answered and hefted Kelvin up to his feet. 

The man wavered slightly, vertigo sinking in as his mind still clawed its way to consciousness. The thrall would let up on its grasp within the hour, leaving Kelvin with no memory of the conversation, and only a minor headache to pay for his troubles. The perfect weapon and tool, Ciel mused as the duo vanished outside the study. 

He shook his head at the thought. Sebastian was more than a weapon and tool. He proved himself repeatedly to the family, and Ciel knew how deep that affection went. For both of them. He knew Sebastian since as long as he could remember. His first memories were that of Sebastian, and the feelings and memories only grew as he aged. 

Sebastian was more than the weapon Rachel intended him to be. He was Ciel’s equal and partner, and Ciel couldn’t imagine his life without him.

**.:|On Water’s Edge|:.**

Ciel looked up from the paperwork stretch out across his desk when Sebastian entered the study. A quick glance at the clock showed the late hour, a time when the shadows stretched long and dark into the night. Blue eyes narrowed at the merman. “Where have you been? I haven’t seen you all day.”

Slowly, Sebastian approached the desk. A pleased look overtook his features, and Ciel felt himself grow on edge. That smile and expression never boded well for anyone, and his eyes flickered over Sebastian’s figure, searching for blood or gore on his clothes. Nothing appeared out of place though and Ciel looked back at Sebastian’s face.

“Sebastian,” he tried again. “What did you do?”

“I eliminated our problem,” Sebastian answered. He placed a cream washcloth on the desk’s surface and flicked it open with an easy gesture.

Ciel leaned forward to peer at it and then collapsed back against the chair as he groaned. “Oh, Sebastian. What did you do?” he asked again. Because really, he didn’t need the merman dropping a severed ring finger in his lap like some cat presenting its kill for him to review. 

“I just visited him,” Sebastian answered.

“Nothing is ‘just’ with you,” Ciel stated. “Case in point. I have Viscount’s, I assume, finger sitting on my desk like a prize.”

Sebastian frowned. “He was not using it. I do not understand why it is a problem.”

“He’s already in prison, Sebastian,” Ciel said and rubbed his hand over his face. “How did you even get in there?”

“Undertaker.”

A heavy sigh. “I don’t know why I even asked.” Ciel poked the finger with a pen and couldn’t stop the small smile that threatened to ghost across his lips. He hated to admit it, but the severed finger showed progress. Because it was just a finger, not a body laid in his lap. Sebastian curbed his desire to kill a threat to his pod, and instead, sought his revenge in other ways. “But why the ring finger?”

“Because it belonged to the ringleader,” Sebastian answered. “And rings are not to be trusted.”

He looked so proud of himself that Ciel couldn’t bring himself to tell Sebastian otherwise. Instead, he circled around the desk and leaned up to run his hand through dark locks. “Thank you,” he murmured and pressed his lips to Sebastian’s. 

Arms wrapped around his waist, drawing him closer and encompassing him in warmth, so that Ciel felt the sense of home and protection. Because home was where Sebastian was.

**Author's Note:**

> Warning for dubious consent in that Rachel and Undertaker force/trick Sebastian to undergo a magic spell that inflicts pain upon his transformations between human and merman.


End file.
